Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2014
Mar. 16, 2015
Jun. 30, 2014
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2014    
Entity Registrant Name REXAHN PHARMACEUTICALS, INC.    
Entity Central Index Key 0001228627    
Current Fiscal Year End Date --12-31    
Entity Filer Category Smaller Reporting Company    
Document Fiscal Year Focus 2014    
Document Fiscal Period Focus FY    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Public Float     $ 147,704,168dei_EntityPublicFloat
Entity Common Stock, Shares Outstanding   179,210,246dei_EntityCommonStockSharesOutstanding